The part you're missing (and what I think kls is getting at) is that groupthink is not exclusive to religion. A group of people will gravitate towards each other and stop critically thinking. It sucks, but it's human nature.

Atheists are just as capable of groupthink as any other group (conservatives, liberals, environmentalists, capitalists). And just as religion has been used, and still continues to be used, to justify some truly horrible things; the militant desire for the elimination of religion can be just as bad. Sitting around pointing fingers at a very large and varied group of philosophies doesn't really do any good...

In the parent post you mention we burned Toyota at the stake for a faulty floor mat, and then in the same sentence say "we pay no mind to the religious implications of our world's enormous head counts all tied to religion." What do you propose? We burn those religious at the stake? Because your groupthink of atheism makes you feel superior (saved)? Because critical thinking is king, and those that you deem unable to do so are inferior (not saved)?

Scary, and almost religious...